condition mean min max ZT0-3 1.34757698625 1.22227817 1.4728758025 ZT4-7 1.56894265775 1.468650568 1.6692347475 ZT8-11 1.65156007975 1.540614181 1.7625059785000001 ZT12-15 1.6870380710000001 1.5624641220000002 1.81161202 ZT16-19 1.68008927625 1.380583357 1.9795951955 ZT20-23 3.30172067925 2.970105126 3.6333362325